Method for prediction and control of tire uniformity parameters from crown thickness variation

Abstract

Improved and more easily implemented methods for predicting uniformity parameters such as uneven mass distribution, radial run out and high speed radial force variation utilize other measurements such as the tire crown thickness variation. When high speed radial force variation is calculated, low speed radial force variation is also measured. Tire crown thickness variation can be measured in different fashions depending on the particular tire manufacturing process employed. By electronically determining resultant uniformity parameters, tires can be improved by rectification to address the uniformity levels. In addition, tire manufacturing can be improved by altering the resultant location of tire crown thickness variation relative to other aspects of the tire and / or tire manufacturing process.

Description

FIELD OF THE INVENTION[0001]The present subject matter generally concerns technology for using crown thickness variation measurements to characterize different harmonic components of tire uniformity performance parameters, such as radial run out, uneven mass distribution and high speed radial force variation. Characterization and prediction of such tire uniformity parameters and others may be used subsequently to characterize or correct manufactured products and / or to improve manufacturing aspects thereof.BACKGROUND OF THE INVENTION[0002]Tire non-uniformity relates to the symmetry (or lack of symmetry) relative to the tire's axis of rotation in mass, geometric or stiffness characteristics. Conventional tire building methods unfortunately have many opportunities for producing non-uniformities in tires. During rotation of the tires, non-uniformities present in the tire structure produce periodically-varying forces at the wheel axis. Tire non-uniformities are important when these force...

AI Technical Summary

Benefits of technology

The present patent provides improved methods for electronically predicting certain tire parameters such as high speed radial force variation and uneven mass distribution based on measured values of tire crown thickness variation. These methods involve measuring the crown thickness variation for the tire, identifying one or more tire parameters associated with the tire, and calculating the uniformity parameters for the tire from the measured crown thickness variation and the identified tire parameters. The methods can be used to characterize tires and improve the determined levels of uniformity parameters by altering the relative location of different tire components or tire manufacturing aspects relative to the location of the crown thickness variation.

Problems solved by technology

Conventional tire building methods unfortunately have many opportunities for producing non-uniformities in tires.

During rotation of the tires, non-uniformities present in the tire structure produce periodically-varying forces at the wheel axis.

Tire non-uniformities are important when these force variations are transmitted as noticeable vibrations to the vehicle and vehicle occupants.

Many different factors can contribute to the presence of non-uniformities in tires, even when the tires are built under seemingly identical process conditions.

Direct measurement of tire HSU parameters, including HSRFV, however, has been difficult and quite costly, making industrial control rather difficult.

These correlations have ranged on a continuum from purely phenomenological to purely statistical in nature, but many have had only limited success.

Although this approach has proven value, the functional model employed in the Zhu '816 patent can sometimes be difficult to implement in practice.

In addition, such model does not account for certain aspects of crown deformation.

Still further, modeling the tire as a simple ring fails to account for differences in tire structure and performance over a range of lateral locations across a tire crown.

Although known technology for characterizing tire high speed radial force variation and uneven mass distribution and affecting associated aspects of tire manufacturing have been respectively developed, no design has emerged that generally encompasses all of the desired characteristics as hereafter presented in accordance with the subject technology.

Images